This invention relates to a device for regulating the delivery of a fuel injection pump of an internal combustion engine.
In particular, the invention concerns such a regulating device of the kind which comprises: a control member movable in dependence upon the speed of the engine; a regulating member for adjusting the delivery of the injection pump; a transmission lever for transmitting movement of said control member to said regulating member, said transmission lever having its ends pivotally connected to said control member and said regulating member respectively; a casing housing said control member, said regulating member and said transmission lever; a pivot having a geometric axis, said pivot being mounted on said casing for rotation about said geometric axis; a spindle connected to said pivot for rotation with said pivot, said spindle being parallel to and eccentric with respect to the geometric axis of said pivot, said transmission lever being freely rotatably mounted on said spindle intermediate the ends of said transmission lever; and actuating means sensitive to a controlling fluid pressure for rotating said pivot, thereby to move said regulating member to adjust the delivery of the injection pump in response to changes in said controlling fluid pressure.
Devices of this kind are known and are disclosed, for example, in U.S. Patent Application No. 362,360 filed 21st May 1973. The eccentricity of the transmission lever-bearing spindle in relation to the pivot enables the injection pump delivery or rate of flow to be corrected in dependence upon the controlling fluid pressure, particularly at full load. This correction is generally effected in dependence on the atmospheric pressure or on a supercharging air pressure, such supercharging air being delivered to the engine by a compressor or a turbo-compressor driven by said engine.
The prior-art devices have disadvantages, however, particularly in as much as they have relatively long response times and relatively low sensitivity.